1. Field of the Invention
The present invention relates to a solid-state image sensor and camera.
2. Description of the Related Art
Japanese Patent Laid-Open No. 2001-250931 discloses a solid-state image sensor having a configuration in which N neighboring pixels form one group, and one microlens is located on N pixels which belong to an identical group, as a solid-state image sensor appended with a focus detection function based on a phase-difference detection method.
In the solid-state image sensor described in Japanese Patent Laid-Open No. 2001-250931, since transistors included in pixels are located on the light-receiving face side, an area of a light-receiving unit is limited by transistors and wiring patterns. For this reason, as a pixel size is reduced, it becomes difficult to obtain sufficient sensitivity.